Light signal



Jan. 21, 1 30. A. w. FISHER- 1,744,319

LIGHT SIGNAL v Filed June 18 1925 Q Q 7J2 INVENTORQ 5 Q-WM,

M ATTORNEY Patented Jan. 21, 1930 UNITED STATES PATENT OFFICE ARTHUR W.FISHER, F WILKINSBURG, PENNSYLVANIA,

ASSIGNOR TO UNION SWITCH &; SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA,A CORPORATION OF PENN- SYLVANIA LIGHT SIGNAL Application filed June 18,1925.

My invention relates to light signals, and particularly to signals ofthe type comprising a units.

I will describe one form of light signal embodying my invention, and onemethod of constructing the same also embodying my invention, and willthen point out the novel features thereof in claims.

I11 the accompanying drawing, Fig. 1 is a View showing, in frontelevation, one form of light signal embodying my invention. Figs. 2 and3 are detail views showing, in elevation and in vertical section,respectively, one of the mounting rings of the signal shown in Fig. 1.Fig. 4 is a sectional view along line IV-IV of Fig. 1 showing therelation to the Various parts during assembly of the signal. Fig. 5 is aView similar to Fig. 4, but showing a signal unit in place after the signal is assembled.

Similar reference characters refer to similar parts in each of theseveral views.

Referring first to Fig. 1, the signal comprises a supporting plate A ofcast aluminum or other suitable material which is here illustrated ascircular in shape. Attached to this supporting plate, in spaced relationabout its edge are a plurality of light projecting signal units, hereillustrated as eight in number and each designated in general by thereference character B. Each signal unit 13 (see Fig. 5) comprises aflange 2 attached r to the plate A by screws 1 and carrying the usualdoublet lens C comprising a front lens 3 and a rear lens 4. The flange 2also carries a cover 6 of any suitable material. A

source of light, here shown as an electric lamp is supported by flange2, and located inside the cover 6 and at the focus of the doublet lensC. It follows that when lamp 5 is lighted a beam of substantiallyparallel rays of light is projected along the optical axis of the signalunit. The lamps 5 of the various plurality of light project-ing signal(Figs. 2 and 3) having a hub Serial No. 38,114.

signal units B may be controlled in any desired manner.

The supporting plate A is mounted in any suitable manner so that theoptical axes of the signal units 13 are directed toward the point orpoints from which the signal indication is to be observed. It will beplain however, that since the beam projected from each signal unit ismade up of substantially parallel rays, it is desirable that the opticalaxes of all the signal units be parallel so that all the signal beamsare projected in the same direction. This is necessary to insure thatthe brightness of all the signal units will be the same when observedfrom a distance.

To accomplish this adjustment I construct the signal as follows:

The supporting plate A is provided with a hole 7, (see Fig. 1) for eachsignal unit, into each of which holes I float a mounting ring 8 8 and aface 8 which is finished, by grinding or otherwise, to a true plane.

In assembling, I place a short screw 9 in each of two screw holes 9* inplate A. The mounting rings 8 are all laid on a horizontal surface plateD which has a top face 10 finished to a true plane. A ring 11 of softmaterial such as felt is placed around the outside of each mounting ring8. The supporting plate A is then placed over the mounting rings, theheads of the screws 9 being inserted in holes 13 in the ring to insureproper location of the rings. With the parts in this position it will beseen that all of the mounting rings 8 have their finished surfaces 8 inengagement with the top of the plate D, and hence all of these finishedsurfaces are in the same true plane. A mass of material 12, such asmolten lead, which will take a permanent 'set is poured into the spacebetween each mounting ring and the supporting plate A, the felt ring 11preventing the escape of this material. When the lead freezes or setsthe rings 8 are all rigidly attached to the supporting plate A, and ofcourse all have their finished faces in the same true plane. The studs 9and the felt rings 11 are then removed.

The inside surface 2 of the flange 2 of each signal unit B is finishedto a true plane, and the parts of each unit are so arranged that theoptical axis of the signal is perpendicular to this surface. lVhen thesignal units are bolted in place by bolts 1 this finished surface ofeach flange engages the finished face of the associated mounting ring8,'Wlll'(3l1 insures that the optical axes of allthe signalswill beparallel.

One advantage of my invention is that separate adjustment of each signalunit in assembling the complete signal is unnecessary. One signal unitmay be removed; and another bolted on in its place without disturbingthe adjustment. of the signal in any way.

Another advantage of my invention 1 is that the large supporting plate"*Aneed' not be accurately finished, thereby eliminating considerableexpense and complication in manufacture.

Although I haveherein shown and described only one form of 'light-signalembodying my invention and only one method of constructing such signalsalso embodying my invention, it should be understood that variouschanges and modifications may be made therein within the scope ofthea-ppended claims without departing from' the spirit and scope of myinvention.

Having thus described my invention,'-what I claim is:

1. A light signal comprising-an unfinished supporting plate, a plurality'ofmounting rings each having a finished face, means for attaehingsaidrings to said plate with said faces all in the same plane, and aplurality of signal units one attached to the finished face of each saidmounting ring.

2. A light signal comprising an'unfinished supporting plate having aplurality ofholes, a plurality of mounting rings each comprising a huband a finished surface, the hub of one of said mounting rings beinginserted in each hole in said supporting-plate, means interposed betweeneach mounting ring and said supporting plate for rigidly fastening saidrings in such positions thatall said finished surfaces lie in one plane,and a plurality of signal units one attached to'the finished surface ofeach said mounting ring.

3. A light signal comprising an unfinished supporting plate, twomounting rings each having a finished face, means forattaching saidrings to said supporting plate with said faces both in the same plane,two signal units each having a finished surface atapredetermined anglewith the optical axis of'the signal, and means for clamping said twosignal units against said two mounting rings, respectively, so that thefinished snrfaceof ea'ch ARTHUR IV. FISHER.

